8 Types of Roommate Rules to Help Keep the Peace at Home

Roommates who get on each other's nerves may make for adorable sitcom fodder, but in real life, it's a drag to live with someone who eats your ice cream or can never round up the rent on time. But having a harmonious relationship isn't about finding the perfect roommate -- because, let's face it, that doesn't exist. Instead, it's about laying down some roommate rules right off the bat.

To avoid some of the most common co-habitation squabbles, consider clearing the air by establishing roommate rules for these key issues.

1. Money, money, money

Before you both move in and start eyeing the biggest bedroom, probably the biggest roommate rule has to do with the rent.

"Write out a clear agreement on how much, in what form, and when your share of the rent is to be paid," suggests Patricia Farrell, a licensed clinical psychologist in Tenafly, NJ.

Make sure you consider what will happen if one of you doesn't pony up the expected portion by the specified time. Should you each pitch in an extra half-month or month's rent upfront in case that worst-case scenario arrives?

Don't feel awkward addressing these "what ifs," by the way. You're doing so only to avoid an ugly scenario in the future. And if someone balks at setting up strict rent guidelines, "you probably don't want them as a roommate," Farrell points out.

2. Refrigerator rights

Let's face it, even the best friendship can go south when ketchup bottles aren't capped or the last piece of Death by Chocolate cake is pilfered. To keep the peace, "keep one side of the refrigerator for you and the other for your roommate, having some common areas for bottles and jars," advises Jeanette Raymond, a licensed psychologist in Los Angeles. Then, agree to clean out the fridge every three to six months -- together.

"That way," says Raymond, "both of you are equally responsible and neither feels nagged, made to feel ashamed, or has all their food thrown out by an angry roommate."

3. Overnight guests who overstay

Friends staying over for long periods of time and not paying rent? That can be a deal breaker.

"An occasional overnight guest may be OK, but someone sleeping on the couch for weeks is not OK," Farrell says. Better set some boundaries before you end up with another person (or two) crashing in your living room. Doing so will avoid a verbal dust-up (or claustrophobia) in the future.

4. Different views of utility usage

Maybe your roomie cranks the air conditioning 24/7 and you're more money-conscious. Or you take long, leisurely showers, and your roommate points out that there's a surcharge on water because of the drought.

"AC and lights not turned out are two major problems," says Farrell. "Just paying 50-50 on utilities may not be enough. One of you could start resenting that you're shelling out more to cover the other's habits. A better solution? Figure out a fair percentage to pay and agree on how they'll be used. For instance, if you're the one who watches cable into the wee hours, maybe you agree to a 60-40 split and to turn it off by midnight.

5. 'Pet-free' areas in the house

Even if you're living with someone who insists that she loves cats, you can't assume she wants your tabby sleeping on her pillow.

"Pets should not be allowed in a roommate's bedroom or bathroom," says Raymond. "Ensure clear boundaries that respect each other's space." FYI, that also means keeping Fluffy off furniture you both share, like the living room couch.

6. Privacy -- everyone needs some

Never enter your roommate's bedroom without permission or an invitation, Raymond advises. You might also think about keeping (locked) separate closets and drawers in common living areas.

"That way," says Raymond, "you create a safe and private place for personal belongings that don't fit in the bedroom."

7. Household chores

Who unloads the dishwasher? Or puts out the trash or mows the lawn? Figure out household chores from the get-go; don't wait until one of you starts complaining #IwishIlivedbymyself. Divvy up chores, then put them on a calendar so you both can keep track.

8. Schedules that don't align

If you and your roommate have different sleep habits, work schedules, or personalities, deciding on acceptable noise levels could be your biggest challenge.

Start off by sharing your weekly schedules so you can prepare for (and adapt to) each other's needs, says Raymond.

For instance, if your roommate always works late on Friday nights, that could be your prime opportunity to host your weekly improv group. And if your roommate knows you have an important deadline coming up, she can arrange to rewatch the last season of "Game of Thrones" elsewhere.

"Being proactive facilitates a smoother and less stressful co-existence," Raymond notes. A good pair of noise-canceling headphones won't hurt either.